Improvement in piano-forte actions



A. K. HEBARD.

Piano-Forte Actions.

N0.145,417. Patented Dec.9,1873.

itnesses. v lnvenlor. 7i 62%;; WW4 4/ I "M/ Q $44? UNITED STATES PATENTOFFICE. Y

ALBERT K. HEBARD, OF CAMBRIDGE, MASSACHUSETTS.

IMPROVEMENT IN PIANO-FORTE ACTIONS.

Specification forming part of Letters Patent No. 145,4l7, dated December9, 1873; application filed September 13, 1873.

To all whom it may concern:

.Be it known that I, ALBERT K. HEBARD, of Janibridge, Middlesex county,in the State of Massachusetts, have invented an Improvement inPiano-Forte Action, of which the following is a specification:

This invention relates to the joints of pianot'orte actions, but moreparticularly to that part of the actions of piano-fortes called theflange; and consists of a flat metal spring properly secured on the toppart of the flange, the spring acting, through the regulatingscrew uponthe under portion of the split end of the flange, in such a manner as togive to the hammer-stem pin an elastic or yielding bearing-surface,thereby preventing sticking, so-called, and also rattling or noise.

In the accompanying plate of drawings my improvement in piano-forteactions is illustrated, Figure 1 being a side view of the flange andhammerstem with my attachment; Fig. 2, a top view of the same; and Figs.3 and 4, plan and edge view s, respective] y, of the spring itself.

A in the drawings represents a flange, such as is generally used in themanufacture of piano-forte actions, with the end B sawed or splithorizontally into two parts, 0 and D, as far as the hole E, which hole Eis bored sufliciently near the bottom part of the flange to give anelasticity or spring to the part D. F and G, respectively, show thehammer-stem and butt, hung by pin H to the flange between the two parts0 and D; I, the screw securing the flange A to rail K; and L, theregulating screw. So far, the above is the common flange in use, withthe exception, in this instance, that the portion of the flange wherethe pin 11 turns in its bearing is not bushed, M, a flat spring, securedat one end by the screw I on the upper side of flange A; at its otherend is a slot, 0, through which passes the regulatingscrew L. Theregulating-screw L also passes freely through the upper part, 0, offlange A, as shown at d, and screws into the lower part, D. The springM, when in its natural position, and secured to the flange A by screw I,is, as shown in Fig. 4, elevated at its end f; and, when properlyadjusted, is screwed down by the regulating-screw sufficiently to causethe proper upward pressure and firmness of the part D against the pin H,by the elasticity of the spring, and yet leaving space enough betweenthe end of spring and the flange to allow of further downward movementof the spring, if desired, for any purpose. In regulating the flange A,without any spring attachment for the right movement of the hammer-steinand butt, the screw L is turned in suffieiently to cause the requisitetightness between the two parts 0 and D on the pin H, so that the butt Gwill be free to play, and yet not loose enough to allow of a noise orrattle. W hen so fixed, the parts 0 and D are rigid, as it were, asregards each other, being prevented from movement by the regulatingscrew; and, if any moisture or dampness is in the air, the wood of whichthe flange is made is more or less affected accordingl y, and expandingor swelling the two parts 0 and D, obviously brings them nearertogether, thus creating more friction on the pin H, and causing it tostick, by reason of the rigidity, as above stated; and, if it becomestoo dry, the pin in its bearing-surface is loose and rattles more orless. Now, with the spring attached to the flange, as above described,these troubles are entirely obviated. The regulation of the movement ofthe hammerstem is performed as in the usual way, but the bearing upagainst the pin of the lower part, D, is controlled by the elasticity ofthe spring M; and, if dampness or dryness should affect the two parts 0and D, they would not bind on the pin H or rattle, because the spring,being of suflicient elasticity, would allow the lower part, I), amplemovement either upward or downward to relieve the additional pressurecaused by the swelling of the wood upon the pin H, or preserve to thebearing the requisite pressure to prevent noise or rattle.

By the use of the spring M many advantages are attained, among which arethe following: The bushing around the pin is dispensed with, saving,thereby, expense in manufacture, as the bearing or friction against thepin H is always firm and elastic enough to prevent noise, and yet befree for the proper movement of the hammer-stem. The hammerstem butt caneasily be removed from the flange, if desired, as, by hearing down onthe butt, the parts 0 and D can be separated sui ficiently to allow thepin free movement from its position without altering the adjustment ofthe regulating-screw, which heretofore has been impossible. The end ofthe sprin M, where secured to the flange, serves also as a washer to thescrew-head, preventing its sinking into the flange, and holding itfirmer on the rail. Also, there is no sidewisc movement to thehammer-stem, as the pin H, on which the hammer-stem swings, has, for itsbearingsurface, the hard wood of the flange, rather than, as fiiirmerly,the cloth bushing.

I am aware that a metallic arched spring has been arranged between theparts composing the butt-hinge; such I therefore disclaim. My spring issecured on the top surface of the butt-hinge by a screw, and its frontslotted end embraces the set-screw, aml has a ALBERT K. URI-KARI).\Yitnesses:

J. l. McELnoY, EDWIN W. -3RowN.

